Evening star. [volume] (Washington, D.C.) 1854-1972, 1887-03-26
CITY AND DISTRICT.
a BOOK CREEK PHILANTHROPISr.
A Strange Insecs Discovered by a Wash.
fngton EmtOusOlOgist.

now rHH BYpRorsYcHE SETS rs TRAPS FOR THE
LARvAH OF THE BLACK FLY.-A LITTLE CREATURE
THAT AvKRTs GREAT PLAGUE FROM TEE NATION Al
CAPITAL
At the meeting OF the Biological Society. Mr. 7.
O. Howard described what he called ssa Rock Greek
Phiianthropist." "In the Banat OF Temeswarr
he said, bordering upon the Danube, and particu-
larry the town Columb acZ In the spring of the
year there come down from the caves in the noun
tatns swarms upon swarms OF biting midges which
fall on the domestic animals and frequently de-
stroy them by scores In the North Woods region
OF the United States and Canada there is another
biting nudge, familiar to all travellers and sports
men by the name OF the sblack-ny,' which is
congeneric with the ny Of the Columbacz This
insect Is the terror Of the wild animals and the
hunter who visits those regions at certain
times OF the year needs some marked protee-
uon against 1t. In the valley OF the Mis-
Sssippi there exists another eongeneric insect,
which, under the name OF the buffalo gnat' has
become such q scourge among the domestic ami
mars OF That region as TO arouse the paternal
interest," OF the government, and an extended In
vcsesatlon INTO It's habits and life history Is now
being carried on by Prof. Riley and his agents and
ASSISTANTS. All these insects belong TO the genus
piaek n.y. or buffalo gnaS.' i've u during the
early portions OF their lives rs small aquatic lar
crcoSc ag aRon minute sr n and other NIL
BLACK FLIES CAPTURED IN THE DISTRICT.
"A few specimens OF a species OF this dreaded
genus have been occasionally captured In the Dis.
tr1ct OF Columbia. Simuliuns renust,fnn say was
caught here by Baron OSten-Sacken years ago and
Iesorded IN his n catalogue IIs occurrence IS very
something unknown II may therefore be OF in
teresf TO record and 1t will probably be surprise
70 most Individuals TO know, that in Rock creek
and probably In other streams In the District the
lAfvB OF a Simultum occur In summer I'm such
countless numbers that II all or nearly all attained
fhafh hon fJl
stream would no longer be the favoritc exploring
ground for the amateur bOtanist an entOmOlogist,
for youth and maiden, and the dwellings,
of the scientific colony on their borders would
scarcely be habitable at certain seasons OF the
year. There Is reason TO suppose that these Larvae
were known to OSten-Sacken twenty years ago,
when he resided in Washington as attache OF
tho Russian legation, and they were rediscovered
last summer by Prof Fulton, OF Brooklyn, and my
se1 attached TO water plants and the rocks In the
litter running portions OF the creek above the
WINDING THE HYpRopsYCHR
SAT the same time, however, It was my good
fortune to md the dwelling places Of a philan-
thropical being which prevents the increase OF
this pest and destroys the black-ny Larvae in such
numbers that the adults are seldom noticed. This
oenencent creature Is slender, carniverouS,
neUropserOus larva Of the genus hydropsyche.
The species has not been determined and may be
undeScrlbed, and the adult insect has not been
found. The iarve are related to the caddis worms.
with funneLShaped mouths spread against the
current All over the upper faces OF the
larger rocks which tilt TO the surface OF
the stream these funnelshaped traps were
spread, and In each one, enSconced In a
straight tight tube behind the funnel. the preda-
ceous arva waits for its victim. The Larvae OF the
black ny travel readily from one point to another
spinning q web through the water. Letting go
their hold from the stem Of aquatic plant or
rom the surface OF rock they float with the cur
rent short distance, still holding to q s1lken
thread attached 70 their first location.
CAUGHT IN THE TRAP.
s1c Is while floating In this way that they are
caught in the traps Of the hydropsyche, and enOr-
nous numbers so perish. The appetite OF the
hydropsyche seems never satisfied; every aquatic
insect which Is washed by the current into the
trap Is devouTed. 1t has no ScrupleS against can
ntbanSm, and an Individual which leaves its own
funnel has very precartouS chance or escaping
from its neighbOr- 1t Is probable that the condI-
tons favorable to the black fly are all in this vi
cfnity favorable TO the hydrOpsyche, so that al
though veri;able plague exists around US in EN-
bryolt Will probably always be ayerted by this
beneficial insect